Fluid control valve

ABSTRACT

This valve control valve comprises a valve body having a central bore therein provided with an intermediate enlarged part and an annular seat, said enlarged part being substantially a first chamber communicated with an inlet in the valve, a valve plug slidably inserted in the bore and having upper and lower cylindrical sliding members, an intermediate brim and a neck portion between the upper sliding member and the brim to define a second chamber there around which is communicated with an out-let of the valve, said brim being positioned in the first chamber and adapted to cooperate with the valve seat to regulate the valve orifice therebetween, and the construction being so arranged that upward and downward fluid pressures within the first chamber to the brim of the plug are balanced and upward and downward fluid pressures in the second chamber to the plug being also balanced thereby moving the plug lightly and easily.

United States Patent 9 1m ()kui 3,756,558 45] Sept. 4, 1973! 1 FLUIDCONTROL VALVE Seiichi Okui, 543 Talsumyagara-cho, lkuno-ku, Osaka, Japan[22] Filed: Nov. 11, 197] [21] 'Appl. No.: 197,648

[76] Inventor:

Primary ExaminerHar01d W. Weakley AttorneyDawson, Tilton, Fallon &Lungmus [5 7 ABSTRACT This valve control valve comprises a valve bodyhaving a central bore therein provided with an intermediate enlargedpart and an annular seat, said enlarged part being substantially a firstchamber communicated with an inlet in the valve, a valve plug slidablyinserted in the bore and having upper and lower cylindrical slidingmembers, an intermediate brim and a neck portion between the uppersliding member and the brim to define a second chamber there aroundwhich is communicated with an out-let of the valve, said brim beingpositioned in the first chamber and adapted to cooperate with the valveseat to regulate the valve orifice therebetween, and the constructionbeing so arranged that upward and downward fluid pressures within thefirst chamber to the brim of the plug are balanced and upward anddownward fluid pressures in the second chamber to the plug being alsobalanced thereby moving the plug lightly and easily.

1 Claim, 5 Drawing Figures minnow 41915 3356558 SHEET 1 0F 5 PATENTEDSEP4 ms SHEET 3 BF 5 IZA PATENTEBSEP 4 ms SHEET l 0F 5 Ill FLUID CONTROLVALVE The present invention relates to a fluid control valve and thisinvention is directed more particularly to the provision of such a valvefor use with cylinders containing gas, such s oxygen, acetylen gas orthe like.

A main object of the present invention is to provide an improved fluidcontrol valve in which the valve plug can be lightly moved withoutreceiving any fluid pressure and fluid resistance thereby correctlycontrolling the flow or pressure of fluid.

And another object of the present invention'is to provide a fluidcontrol valve which is responsive to fluid pressures and changes therate of opening of the valve orifice to control the fluid pressure onthe outlet side in a predeterminate condition.

In carrying out the invention in one aspect thereof, a fluid controlvalve is provided in which the combination comprises a valve body havinga bore therein provided with an intermediate enlarged part and anannular seat, said enlarged part being substantially a first chambercommunicated with an inlet in the valve, a valve plug slidably insertedin the bore and having upper and lowe cylindrical sliding members, anintermediate brim and a neck portion between the upper sliding memberand the brim to define a second chamber there around which iscommunicated with an outlet of the valve, said brim being positioned inthe first chamber and adapted to cooperate with the valve seat toregulate the valve orifice therebetween, and the construction being soarranged that upward and downward fluid pressures within the firstchamber to the brim of the plug are balanced eand upward and downwardfluid pressures in the second chamber to the plug being also balancedthereby moving the plug lightly and easily.

Other objects and advantages of the subject invention will becomeapparent from reading the following detailed description and byreference to the accompanying drawings wherein:

FIG. 1 is a longitudinal sectional view taken along the line in ll inFIG. 2, of the fluid control valve according to the present invention;

FIG. 2 is a plan view of the fluid control valve;

FIG. 3 and 4 are longitudinal sectional view of other embodiments of thevalve according to the present invention; and

FIG. 5 is an enlarged sectional view showing essential parts of thefluid control valve according to the present invention.

The fluid control valve of this invention is genrally designated at andit includes a valve body 1 1 formed of brass or the like. The valve body11 has a longitudinal central bore 14 in which a valve plug 12 isslidably mounted. The central bore 14 has at intermediate portionthereof an enlarged part to form a first chamber 14A which iscommunicated through a passage 18 with an opening 17 of an externallythreaded coupling member 16, the latter being communicated through asuitable duct (not shown) with a cylinder containing a gas, such as anoxygen, acetylene gas and the like. The valve plug 12 comprises an uppersliding portion 12A, a lower sliding portion 128, an enlarged brim 12Cformed at intermediate part of the plug 12 and having an upwardly facingvalve element 13,-and a neck portion 12D formed between the uppersliding portion 12A and the brim 12C to form a second chamber 148there-around, said valve element 13 being preferably formed from nylonor the like. The brim 12C of the plug is positioned in the first chamber14A, and the valve element 13 on the brim 12C, upon movement of thevalve plug 12 engages and disengages a seat 15 for closing and openingthe fluid passage through the valve. The valve body 11 also providedwith a lateral bore 21 which communicates the second chamber 148 with anopening 20 of an externally threaded coupling member 19 which isconnected with means, for example, as a cutting tip or nozzle of thewelding and cutting device by means of a duct. The lower end of thecentral bore 14 is closed by cup 24 having small opening 25, and aspring 22 is positioned in a lower space 23 defined between the end ofthe central bore 14 and the top surface of the cup 24 to upwardly urgethe plug. An upper space defined between the top surface of the plug 12and the downwardly facing end surface of the centrol bore 14 iscommunicated with the outer air by a small opening 40.

Designated at 26 is a housing which has a diaphragm chamber 30 therein.The housing 26 is provided with a threaded opening 39 at the top thereofto which a screw shaft 37 of a handle 27 is threaded. The bottom of thehousing is open and provided with an internal thread. The valve body 11has a top shallow recess or pilot chamber 29 and a top external threadwhich is engaged with the internal thread of the housing. There is adiaphragm 28 which is extended over the end 27 of the valve body 11 andwhich is gripped between that end 27 and an internal flange 26a in thehousing 26. The diaphragm 28 is carried by a push rod 38 at intermediateportion of the back surface thereof, and a lower part of the push rod38' is extended into the upper space 41 through a perforation 42, theextended lower end of the push rod 38 being adjoined to the uppensurface of the valve plug 12. On the lower end of the screw shaft 39, areceiving plate 35 is positioned with a-ball 36 which allows relativerotation between the screw shaft and the receiving plate 35, the latterbeing adapted to receive one end of a spring 34. The spring 34 isarranged between the upper receiving plate 35 and a lower receivingplate 43 mounted on the diaphragm 28. The upper chamber 30A defined bythe diaphragm 28 is also communicated with the outer air by an aperture32, and the pilot chamber29 is communicated with the second chamber 148through a passage 31 and the opening 21.

As illustrated in FIG. 5, the areas of upper and back surfaces of thebrim 12C within the first chamber 14A are equal to each other, so thatdownward pressure in the first chamber 14A to the upper surface and theupward pressure '71 to the back surface are balanced. Furthermore,downward pressure 61 in the second chamber 143 to the plug 12 and upwardpressure 60 to the plug are so intended as to balance. Therefore, thereis no resistance of the fluid in the first and the second chambers tothe plug 12 during its movement.

In FIG. 1, valve closed condition is shown in which the valve element 13of the plug 12 is normally seated on the valve seat 15 and no fluidpressure may pass from the inlet or opening 17 to the outlet or opening20. When the handle 37 is manually roteted clockwise in FIG. 2, thediaphragm 28 deforms downwardly by the depressed spring 34, and the pushrod 38 is pressed down with the plug 12, thereby opening the valvepassage and permitting the possage of fluid from the inlet 17 and out ofthe outlet 20. The rate of opening of the valve passage is small andfluid pressure passing through the valve passage is reduced. When thepressure in the second chamber increases by reason of, for example, flowresistance, this increased pressure is introduced into the pilot chamber29 through the passage 31, raising the diaphragm 28 against pressure ofthe spring 34, whereby the plug 12 is upwardly moved by action of springto reduce valve gap between the valve seat 15 and the valve element 13until] the fluid pressure in the second chamber is reduced bypredetermined pressure. Thus, the fluid pressure in the second chamberis automatically controlled.

It is to be noted that as the plug 12 is moved up and down withoutmeeting with any resistance from the fluid in the first and secondchambers by reason of beforementioned construction, the plug 12 respondssensitively to variation of pressure in the second chamber 14B and itscommunicated parts for varrying the valve gap or orifice. Furthermore,the spring 22 for carrying the plug may be made from small spring steelsufficient to maintain the plug in the position, whereby manipulation ofthe handle 27 will be performed lightly and easily.

In FIG. 3, other embodiment of the fluid control valve according to thepresent invention is shown wherein there is no above mentioned diaphragmmeans and, instead of such means the valve orifice or the rate of valveopening is manually operated by rotating of a handle 27'. Furthermore,another embodiment of the fluid control valve illustrated in FIG. 4 iselectrically controled, that is, the valve orifice in this fluid controlvalve is varried by an electric magnet 75 having a moving core 76. Othercomponents in this fluid control valve are similar to beforementionedfirst embodiment illustrated in FIG. 1.

While the present invention has been illustrated and described hereinwith respected to preferred embodiments, it is not desired to limit theinvention only to the embodiments, but the invention should beconsidered to include all the substilutes, modifications and equivalentswhich are encompassed within the essential part of the invention to beset forth in the scope of the underwritten claim and within the scope ofthe spirit exhibited in the intention of the invention.

What is claimed:

1. A fluid control valve comprising a valve body having an elongatedcentral bore providing first and second chambers and terminating in abottom portion, the first chamber having a transverse dimension greaterthan the transverse dimension of the second chamber, the transversecross sectional area of the second chamber and the transverse crosssectional area of the bottom portion of the bore being equal, the valvebody being provided with a valve seat surrounding the second chamber andseparating the second chamber from the first chamber, an elongated valveplug slidably received in the central bore for longitudinal slidingmovement therein, the valve plug including a first sliding portionslidably received in and sealingly engaging the bottom portion of thebore, a brim portion extending transversely outwardly from the firstsliding portion, the brim portion having an upper surface engageablewith the valve seat to seal the first chamber from the second chamberand a lower surface extending outwardly from the first sliding portion,a second sliding portion slidably received in and sealingly engaging thesecond chamber, and a neck portion extending be tween the second slidingportion and the brim portion and having a transverse dimension less thanthe transverse dimension of thesecond sliding portion, spring meanswithin the bore acting on the valve plug for resiliently biasing thebrim portion of the valve plug against the valve seat, and means on thevalve body for moving the valve plug against the bias of the springmeans whereby the brim portion is moved away from the valve seat, theportion of the upper surface of the brim portion which extends outwardlyof the valve seat when the upper surface engages the valve seat havingan area substantially the same as the area of the lower surface of thebrim portion, the portion of the upper surface of the brim which islocated inwardly of the valve seat having an area substantially the sameas the area of the portion of the second sliding portion of the valveplug which extends outwardly of the neck portion whereby neither thepressure within the first chamber nor the pressure within the secondchamber exerts a sliding force on the valve plug.

1. A fluid control valve comprising a valve body having an elongated central bore providing first and second chambers and terminating in a bottom portion, the first chamber having a transverse dimension greater than the transverse dimension of the second chamber, the transverse cross sectional area of the second chamber and the transverse cross sectional area of the bottom portion of the bore being equal, the valve body being provided with a valve seat surrounding the second chamber and separating the second chamber from the first chamber, an elongated valve plug slidably received in the central bore for longitudinal sliding movement therein, the valve plug including a first sliding portion slidably received in and sealingly engaging the bottom portion of the bore, a brim portion extending transversely outwardly from the first sliding portion, the brim portion having an upper surface engageable with the valve seat to seal the first chamber from the second chamber and a lower surface extending outwardly from the first sliding portion, a second sliding portion slidably received in and sealingly engaging the second chamber, and a neck portion extending between the second sliding portion and the brim portion and having a transverse dimension less than the transverse dimension of the second sliding portion, spring means within the bore acting on the valve plug for resiliently biasing thE brim portion of the valve plug against the valve seat, and means on the valve body for moving the valve plug against the bias of the spring means whereby the brim portion is moved away from the valve seat, the portion of the upper surface of the brim portion which extends outwardly of the valve seat when the upper surface engages the valve seat having an area substantially the same as the area of the lower surface of the brim portion, the portion of the upper surface of the brim which is located inwardly of the valve seat having an area substantially the same as the area of the portion of the second sliding portion of the valve plug which extends outwardly of the neck portion whereby neither the pressure within the first chamber nor the pressure within the second chamber exerts a sliding force on the valve plug. 